Valve replacement may be indicated when there is a narrowing of the native valve, commonly referred to as stenosis, or when the native valve leaks or regurgitates. Examples of valves that may be replaced include heart valves and venous valves. Valve replacement is used to repair or replace a diseased valve. To replace a heart valve, one method is open heart surgery. Another method to replace a heart valve, typically an aortic valve, is transcatheter aortic valve implantation (TAVI), developed to treat high-risk or inoperable severe aortic stenosis patients, which is known to have a poor prognosis clinically. Currently, TAVI is a fast growing procedure, with more than 20,000 patients treated worldwide. It has been recommended as an alternative strategy for patients in high-risk surgical groups. However, one of the technical challenges of TAVI is to reduce the delivery profile and increase the durability of the valve.
One type of prosthetic valve used for open heart surgery is a caged ball type heart valve which utilizes a metal cage to house a silicone elastomer ball and is sutured into place. An example of such a caged ball valve is the “Starr-Edwards” valve manufactured by Edwards Lifescience. When the caged ball valve is implanted as a replacement for a heart valve and blood pressure in the chamber of the heart exceeds the pressure on the outside of the chamber, the ball is pushed forward against the cage end and allows blood to flow through the valve. At the completion of the heart's contraction, the pressure inside the chamber drops and is lower than beyond the valve, so the ball moves back against the base of the valve forming a seal that prevents blood from flowing through the valve.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.